Immunoaffinity Purification of an Acinetobacter baumannii Antigen that Potentially Induce Multiple Sclerosis — 71p — Cane Schmitt, Kelsey Morrison, and Dr. Chun Wu

Multiple sclerosis (MS) is an autoimmune disorder characterized by the immune system’s attack on the myelin sheath of nerve cells. Elevated levels of Acinetobacter baumannii have been observed in MS patients. Our previous in silico studies identified sequence homologies between Acinetobacter baumannii proteins and human Myelin Oligodendrocyte Glycoprotein (MOG) and Myelin Proteolipid Protein (PLP). Western blot analysis revealed that both human polyclonal anti-MOG and anti-PLP IgG antibodies recognize an Acinetobacter baumannii protein around 25 kDa. In this study, we identified the nature of this protein using immunoprecipitation and proteomic analysis. Non-reducing SDS-PAGE analysis of the elute fraction from Protein AG Magnetic Beads, incubated with Acinetobacter baumannii protein mixture and anti-MOG IgG, showed three bands at approximately 23, 24, and 175 kDa. Liquid chromatography-tandem mass spectrometry identified the 24 kDa band as a member of CoA transferase subunit A (MW 23895 Da) and the 23 kDa band as subunit B (MW 22869 Da) of the same protein. The 175 kDa band was confirmed to be a conjugate of this protein and anti-MOG IgG. Similarly, non-reducing SDS-PAGE analysis of boiled beads from Protein AG Magnetic Beads, incubated with Acinetobacter baumannii protein mixture and anti-PLP IgG, revealed two bands at 23 and 24 kDa. Proteomic analysis of these bands is currently underway. The identification of the Acinetobacter baumannii antigen that are recognized by human myelin anti-MOG and anti-PLP antibodies enhances our understanding of the etiology of MS and holds potential for advancing preventive strategies.

Mount Marty College
Dr. Chun Wu